Manner of constructing the pistons of pneumatic springs to be



A. CONNISON.

Car Spring.

Patented Dec. 23, 1841.

N. PETERS. FHOTO UTHOGR H UNITED STAEN eerie ALEXANDER OONNISON, OFBELLEVILLE, NE\V JERSEY.

MANNER 0F CONSTRUOTING THE PISTONS OF PNEUMATIC SPBilNG-S TO BE APPLIEDTO RAILROAD-CARS AND OTHER CARRIAGES OR TO OPERATE AS BUD/ FEES 0RDRAFT- SPRINGS.

Specification of Letters Patent No. 2,395, dated December 23, 1841;Antedated December 20, 1841.

To all whom it may concern:

Be it known that I, ALEXANDER CONNI- soN, of Belleville, in the countyof Essex and State of New Jersey, have invented a new and usefulimprovement in the manner of constructing a pneumatic-spring cylinderand piston to be applied to railroad-cars and other vehicles requiringthe use of springs either for the purpose of sustaining such cars orcarriages or to operate as bumpers or as draft-springs; and I do herebydeclare that the following is a full and exact description thereof.

The spring which I use is dependent for its action upon the elasticityof atmospheric air, or of any other permanently elastic fluid; and ineimoloying it I confine the air within a cylinder, to which I adapt apiston so constructed and packed as to act freely within said cylinderand eflectually to prevent the escape of the air. I am aware that acylinder containing air, and furnished with a piston capable of movingwithin it has already been applied to cars, or carriages to operate as aspring, but I have made certain improvements in the manner ofconstructing and packing the piston, and in its appendages, by which itseiiiciency and the facility with which it is regulated are greatlyincreased.

In the accompanying drawing Figure 1 represents a vertical section of mycylinder and piston through the middle thereof.

A, A, is the cylinder of brass, or other metal, and this is closed atits lower end by a stufling box, B, there being some elastic material ata, a, through which slides a tubular piston rod J. The upper part H, ofthe tubular rod J, is enlarged, as shown in the drawing, and forms apart of the piston; and the piece of metal E, E, constitutes anotherpart of said piston.

I, I, is the space for receiving hemp, or other suitable packing betweenthe parts H, and E. The upper part of the segment II, of the piston isreceived within the recess M, M, in the lower part of the segment E, E,and when these two parts are pressed together, and the upper part of II,is made to slide into the cavity M, the packing in I, I, Will be therebytightened. The main packing of this piston, however consists in a seriesof hemispherical cups of leather, I), D, D, which fit into ahemispherical concavity in the upper side of the segment E, E, of thepiston, while thin edges bear against the sides of the cylinder. Theleather cups D, I), are held in place and forced against the cylinder bymeans of the bolt L, L, which passes through apertures made in themiddle of the leathers and through the tubular rod (I. The head L, ofthis bolt presses upon the leather by its convex under side, and forcesthem out. The lower end of the tubular piston rod J, is sustained at Z),7), by the cross head K, K, or by any other suitable hearing or fixtureon the frame work ofthe car, or other carriage. The screw nut; S, underthis cross head serves to draw down the bolt L, L, and in doing so, thepacking at I, I, is tightened, as are also the leather cups D, D. Thelower part of this apparatus may be differently arranged, and aflixed,and the same effect he produced; the lower end of the bolts L, L, mayfor example be sustained in any convenient manner, and a nut upon it bemade to bear against the lower end of the tubular piston J the effect ofwhich will be to tighten the packing by producing the same action uponit as that above described. The upper end of the cylinder A, is closedby a cap, or cover F, F, resting on its fianch C, C, and attached to itby suitable screws, said cap being rendered air tight by grinding, or bywashers of leather or other suitable substance.

T, T, represents one of the sides of a metallic trough, or saddle,rising from the cap, or cover F, F, and by which to attach the cylinderto the car, or carriage body. This part may be made in any form by whichit will be adapted to the intended purpose.

Into the cylinder A A, air is to be forced by means of a condensingsyringe. For this purpose an aperture is made through the cap of thecylinder, and this aperture is closed by a *alve, which is kept tight bythe elasticity of the contained air. Various kinds of valves may beemployed, but I have used a ball valve, as shown at V; this arrangementis more distinctly represented in Fig. 2, which is a section madethrough the cap in a direction at right angles to that exhibited inFig. 1. In this figure C, C, are the flanches 0f the cylinder, and F, F,the cover, or cap, with its raised sides T, T. The ball valve is shownat N, and an aperture 0, leading from it into the cylinder.

V is a screw within the projecting piece X by which a condensing syringemay be attached, and which may at other times be closed by a tightfitting screw stopper.

In the foregoing description I have contemplated the action of mypneumatic spring cylinder and piston in its application to thesustaining the bodies of cars and of other carriages, it not beingnecessary to point out any particular arrangement for employing it as abumper, or as a draft spring, as every competent machinist can do thiswithout requiring any instruction for that purpse, an air cylinder beingsubstituted for one containing a spiral spring, such as has beensometimes used in the forming of bumper and draft springs.

Having thus fully described the manner in which I construct and arrangethe respective parts of my improved pneumatic spring, cylinder, andpiston, What I claim a sustaining spring for cars, or other carriages,or as a bumper or draft spring, as a substitute for the spiral or othersprings which have been used for those purposes.

And I do hereby declare that I do not intend to limit or confine myselfto the particular form, or construction of the individual parts of theinstrument as herein represented, but to vary these as I may findconvenient While the general combination and action thereof remainunchanged.

ALEXANDER CO'NNISON.

WVitnesses WVILLIAM LEE, GEORGE H. LEE.

